• 식품과학과 산업
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• 제44권2호
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• pp.9-15
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• 2011

• 방사선산업학회지
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• 제8권2호
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• pp.123-132
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• 2014

After the nuclear accident of the Fukushima Dai-ichi Nuclear Power Plants (FDNPPs) on 11 March 2011, a large amount of radioactive materials has been released into the atmosphere and the ocean. A compartment model is used to evaluate the circulation characteristics and the spatiotemporal concentration distributions of radionuclides in the ocean. In the comparison with observed concentrations of $^{137}Cs$ in seawater, calculated concentrations by the compartment model were well agreed with them. On the basis of these results, we performed evaluation of the effective dose and the cancer risk. In the early stage of the accident, the effective doses from ingestion of the seafood near the Fukushima region were much higher than 1 mSv which is the value of the annual effective dose limit to individual recommended by the International Commission on Radiological Protection (ICRP). However, the effective doses by ingestion of the seafood decreased below 1 mSv as distance from the FDNPPs increased and time passed. In addition, it was estimated that the cancer risks by intake of the contaminated marine products were less than natural occurrence probability of cancer. Consequently, it was inferred that the health risk due to the $^{137}Cs$ was low after since mid-term period of the accident.

• 방사선산업학회지
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• 제17권3호
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• pp.283-292
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• 2023

Spent nuclear fuel corresponds to high-level radioactive waste that has high decay heat and radioactivity. Accordingly, Spent nuclear fuel withdrawn from the reactor core is primarily stored and managed in a spent nuclear fuel pool in the nuclear power plant to reduce decay heat and radioactivity. In Korea, most nuclear power plant store all spent nuclear fuel in a spent nuclear fuel pool. For wet storage, there are no defense in depth different with reactor core. The study related to spent nuclear fuel pool accident should be carried out to ensure safety. Therefore, it is necessary to analyze previous study cases related to safety of spent nuclear fuel pool and accident cases to build foundational knowledge. The Objective of this study is to analyze study cases of safety assessment and cases for spent nuclear fuel pool accident. For analyzing study cases of safety assessment, possible phenomena when spent nuclear fuel pool accident occurring identified, Subsequently, study cases for safety assessment about each phenomena were investigated, and materials & methods and results for each study are analyzed. For analyzing cases for spent nuclear fuel pool accident, we analyzed accident cases caused by loss of cooling and loss of coolant in spent nuclear fuel pool. Subsequently, causes and change of water level and temperature by each accident case are analyzed. As a result of the analysis on study cases of spent nuclear fuel pool accident, the results of the study conducted by each research institute were vary depending on the computer code, materials & methods of experiment and major assumptions used in the study. As a result of analyzing cases for spent nuclear fuel pool accident, it was found that accident cases for loss of cooling is more than cases for loss of coolant accident. Even though the types of accident in spent nuclear fuel pool were similar, the specific causes were different by each accident case. All the accident cases analyzed did not lead to severe accidents, such as nuclear fuel being exposed to the air. The result of this study will be used as fundamental data for study on spent nuclear fuel pool accident that will be conducted in the future.

• Nuclear Engineering and Technology
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• 제52권5호
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• pp.984-994
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• 2020

It is reported that about 20% of accidents at nuclear power plants in Korea and abroad are caused by human error. One of the main factors contributing to human error is fatigue, so it is necessary to prevent human errors that may occur when the task is performed in an improper state by grasping the status of the operator in advance. In this study, we propose a method of evaluating operator's fitness-for-duty (FFD) using various parameters including eye movement data, subjective fatigue ratings, and operator's performance. Parameters for evaluating FFD were selected through a literature survey. We performed experiments that test subjects who felt various levels of fatigue monitor information of indicators and diagnose a system malfunction. In order to find meaningful characteristics in measured data consisting of various parameters, hierarchical clustering analysis, an unsupervised machine-learning technique, is used. The characteristics of each cluster were analyzed; fitness-for-duty of each cluster was evaluated. The appropriateness of the number of clusters obtained through clustering analysis was evaluated using both the Elbow and Silhouette methods. Finally, it was statistically shown that the suggested methodology for evaluating FFD does not generate additional fatigue in subjects. Relevance to industry: The methodology for evaluating an operator's fitness for duty in advance is proposed, and it can prevent human errors that might be caused by inappropriate condition in nuclear industries.

• 자원ㆍ환경경제연구
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• 제26권4호
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• pp.549-575
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• 2017

앞으로 우리나라의 발전원 구성은 신정부의 에너지 정책에 따라 석탄화력과 원자력이 감소하고 가스복합과 신재생에너지가 증가할 것으로 예상되며, 그러한 변화로 도시가스 산업에도 변화가 있을 것이다. 본 연구에서는 발전원 변경에 따른 영향을 정량적으로 살펴보기 위하여 석탄화력과 원자력을 각각 가스복합과 연료전지로 대체하는 시나리오를 설정하여 시나리오별로 도시가스 산업이 다른 산업에 미치는 경제적 파급효과의 변화를 분석하였다. 이 과정에서 정책의 영향이 나타날 시점을 고려하여 2030년 산업연관표를 추정하여 분석을 실시하였다. 분석 결과 가스복합으로 발전원을 대체하는 경우는 전체 산업에 유발하는 생산이 감소하고 연료전지를 사용하는 경우 증가하는 것으로 나타났으며, 모든 시나리오에서 전체 산업에 유발하는 부가가치는 동일한 것으로 나타났다. 이러한 결과는 발전원 변경 시, 변경 영향이 상대적으로 작게 나타나며 진입장벽이 낮은 가스복합을 단기적으로 활용하고, 장기적으로는 경제적 파급효과가 큰 연료전지를 활용하는 방안이 적절함을 의미한다.

• 한국태양에너지학회 논문집
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• 제40권4호
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• pp.23-33
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• 2020

The loss in photovoltaic power due to hailstorms has been highlighted as a major issue in the sustained growth of the PV power plant industry. This study investigates the safety of a solar module by conducting a numerical analysis of a hail test according to the IEC 61215 standard. Our study aims to elucidate the detailed behavior between the ice and solar modules and the micro-cracks forming on solar modules during hailstorms. To analyze the impact of hail, we used the ANSYS AUTODYN software to evaluate the impact characteristics on a solar module with different front glass thicknesses. The simulations show that a solar module with a glass thickness of 4.0 mm results in excellent durability against hail. The results indicate the feasibility of using simulations to analyze and predict micro-cracks on solar modules tailored to various conditions, which can be used to develop new solar modules.

• 방사선산업학회지
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• 제17권1호
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• pp.11-17
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• 2023

Waste generated during the dismantling of nuclear power plants is not only diverse in types such as metal, concrete, soil, but also in a large amount, requiring systematic and efficient management. It is very important to quickly and accurately measure radioactive contamination of wastes generated simultaneously at the decommissioning site, classify them by level, and make decisions so that they can be disposed of in accordance with related laws and regulations. In this paper, for the technical and economic aspects of recycling of radioactive metal waste generated during the dismantling of nuclear power plants, we propose a management system that can measure the radioactive contamination by shape of metal waste at the decommissioning site and automatically classify it according to the presence or absence of contamination. Accordingly, a system for collecting information on metal samples such as weight measurement and shape acquisition of metal waste, measurement of radioactive contamination and identification of nuclides, and an automatic classification system according to radioactivity measurement results were described.

• 방사선산업학회지
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• 제18권1호
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• pp.9-14
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• 2024

In order to thoroughly verify the denuclearization of the Korean Peninsula, it is urgent to develop technology capabilities to monitor, detect, collect, analyze, interpret, and evaluate nuclear activities using nuclear materials and secure nuclear transparency. The IAEA is actively using seal technology to maximize the efficiency of safety measures, and currently uses metal cap, paper, COBRA, and EOSS as seal devices. Unlike facilities that comply with safety measures requirements, such as domestic nuclear facilities, facilities subject to denuclearization are likely to have various risk environments that make it difficult to apply safety measures, and there is a high possibility that continuity of knowledge (COK) such as damage, malfunction, and power loss will not be maintained. This study aims to develop a real-time active seal device that can be applied in such special situations to enable immediate response in the event of a similar situation. To this end, the main functions of the real-time seal device were derived and applied, and a commercialized seal device and operation software. The real-time seal technology developed through this study can be applied to all nuclear facilities in South Korea, especially used as storage equipment for dry cask storage facilities of heavy water reactor's after fuel, and it is believed that unnecessary radiation exposure by inspectors can be minimized.

• 방사선산업학회지
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• 제5권2호
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• pp.185-189
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• 2011

As nuclear industry has been developed, a various types of radiological contamination has occurred. After 9.11 terror in U.S.A., it has been concerned that terrorists' active area has been enlarged to use nuclear or radioactive substance. Recently, the most powerful earth-quake stroke, which triggered a massive tsunami in Japan and then Fukushima nuclear power plant reactor has suffered from a serious accident in history. The Fukushima reactor accident has occurred an anxiety of radiation leaks and about 170,000 people have been evacuated from the accidental area near the nuclear power plant. For these reasons, a social chaos can be occurred if radiological contamination occurs to the supply system for the drinking water. As such, the establishment of the radiation monitoring system for the city main water system is compelling for the national security. In this study, a feasibility test of radiation monitoring system which consists of unified hybrid-type radiation detectors was experimented for multi detection system by using gamma-ray imaging. The hybrid-type radiation sensors were fabricated with CsI(Tl) scintillators and photodiodes. A preamplifier and amplifier was also fabricated and assembled with the sensor in the shielding case. For the preliminary test of detection of radiological contamination in the river, multi CsI(Tl)-PIN photodiode radiation detectors and $^{137}Cs$ gamma-ray source were used. The DAQ was done by Linux based ROOT program and NI DAQ system with Labview program. The simulated contamination was assumed to be occurred at Gapcheon river in Daejeon city. Multi CsI(Tl)-PIN photodiode radiation detectors were positioned at the Gapcheon river side. Assuming that the radiological contaminations flows in the river the $^{137}Cs$ gamma-ray source has been moved and then, the contamination region was reconstructed.

• 자원ㆍ환경경제연구
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• 제25권3호
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• pp.449-470
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• 2016

본 연구는 14개 원전 운영국, 22개 제조업군을 대상으로 전원에서 원전이 차치하는 비중의 변화가 제조업 성장에 미치는 영향을 분석하였다. 한 국가의 원전비중 변화는 전력가격의 변화를 통하여 산업의 부가가치와 생산량에 영향을 미친다는 가설을 동태적 패널데이타 모형을 이용하여 분석하였다. 주요 6개국의 분석결과에 따르면 원전비중이 1%p 증가할 경우 전기 가격은 0.8%감소하는 것으로 추정이 되었다. 또한 주요 6개국에 국한된 분석 결과에서는 원전 비중이 1%p 증가하였을 경우 산업별 부가가치 및 생산량은 단기에 0.16% 및 0.23% 증가하였고 장기적인 효과는 0.51% 및 0.85%에 달하였다. 전력요금 절감을 통하여 원전이 산업경쟁력에 기여하는 효과는 전력시장의 제도에 따라 달리하는 것으로 추정이 된다. 영국과 일본과 같이 전력가격 수준이 높고 변동폭이 큰 국가에서 전력요금 절감을 통한 산업경쟁력 제고가 크게 나타나는 반면, 원전 축소정책을 지향하는 독일에서는 전력요금 절감보다는 안정적인 전력수급을 통하여 산업경쟁력에 기여하는 것으로 본 논문의 결과를 해석할 수 있다.